Worth the upgrade? (GTX660 to GTX770)

Currently I have a GTX660 SC (with 2gb GDDR5, and that awful blower that pretty much lets the card overheat). A friend of mine that has a GTX770 SC (with 2gb GDDR5 and the EVGA ACX Cooler) he has offered the card to me at a price of 280- this new card will NOT have more g-ram than my current card. Is this new card worth my money or should I hold out and get a R9 290? 

I would personally hold out and get a 290

That is an amazing deal on a 770. And with how bad the 290's stock fan is, I'd go for it. But if you want to go 290 wait for an aftermarket cooler. The stock is unusable.

Well that goes without saying. I already have a blower card; and I want to go back in time and beat the past me within an inch of my (his) life.